there's no progression slowing pd treatments likely because there has been no diagnostic test for presymptomatic pd. if i had known i was developing pd years before i exhibited symptoms it would have been invaluable for me, my relatives who might develop pd and my family. and for researchers developing a preventive treatment, plus would supply more DNA samples to look for genes that predispose you to pd. and yes, i would certainly live my life differently, certainly to the fullest. and if the test was cheap enough it could be done often enough so researchers could determine what environmental factors might be causing pd rather than guessing at something that happened in the past. if i could help 1 person avoid pd then the test is worth it.